"Three turtles in a bar" joke
Three turtles stop in at a bar on a hot day for a beer. While they're waiting they notice that it has started to rain.
"Freddy," says the biggest turtle to the smallest, "go home and fetch our umbrellas."
"No," replies Freddy, "because if I leave you'll drink my beer."
Both of the other turtles promise they would never do such a thing, so Freddy grudgingly gets down from the stool and heads for the exit. Two weeks go by, as the turtles stare thirstily at Freddy's untouched beer in front of them.
Finally one turtle says to the other, "Oh, let's go ahead and drink Freddy's beer. We can tell him it was never delivered."
A voice from up near the front of the bar says, "If you do, I'm not going home for the umbrellas!"
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